"Classes" "f" "rf(%)" "cf(%)"
"[10, 020)" 8 3.43 3.43
"[20, 030)" 18 7.73 11.16
"[30, 040)" 29 12.45 23.61
"[40, 050)" 39 16.74 40.34
"[50, 060)" 47 20.17 60.52
"[60, 070)" 39 16.74 77.25
"[70, 080)" 28 12.02 89.27
"[80, 090)" 18 7.73 97
"[90, 100)" 7 3 100